iommu/rockchip: Fix zap cache during device attach

iommu/rockchip: Fix zap cache during device attach

rk_iommu_command() takes a struct rk_iommu and iterates over the slave
MMUs, so this is doubly wrong in that we're passing in the wrong pointer
and talking to MMUs that we shouldn't be.

Fixes: cd6438c5f844 ("iommu/rockchip: Reconstruct to support multi slaves")
Cc: [email protected]
Signed-off-by: John Keeping <[email protected]>
Tested-by: Heiko Stuebner <[email protected]>
Reviewed-by: Heiko Stuebner <[email protected]>
Signed-off-by: Joerg Roedel <[email protected]>